Anti-offset device for printing-presses.



C. HENDERSGN ANTI-OFFSET DEVICE FOR PmNTmG FRESSES.

APPLICATION FILED NOV. i. 1913.

Patented. Nov. 16, 1915.

enr ch eannnnnnnnson, OF can PARK, ILLINOIS, essronon To THE MIEHLE PRINTING rnnss & MANUFACTURING COMPANY, or CHICAGQ-ILLINOIS, A CORPORATION or nnri-orrsnrn'nvrcn roe, ."PRINIQINGLPEESSES.

Specification of Letters Patent. tej i1 q 1915 Application area nu emb; 1 1913. Serial No. 798,641.

5..Ill-inois..have invented certain new and use ful Improvements 1nAnt1-Offset Devicesfor it Printing-Presses, of which the following is a SlIQClfiCEltlOIl- I *In'the case -of perfecting presses,- where both sides of the paper are printed in rapid success on upon companion cylinders a difficulty encountered has been the tendency of the ink taken up by the second cylinder from the printed surface of the preceding sheet to offset upon the surface of the next sheet. 'Yarious expedients have beenresorted to to overcome this difficulty, but

without being completely successful.

It iskn'own that. starch and some other 0 powders when. applied to an inked surface will dry the same by a blotting action and when reinoved will leave the surface in dry conditionso the ink will notoffset. It is not practicable. however, to apply such pow- 5 derby hand to the second cylinder of .per-

fecting presses between the pi' intiiigof each sheet, and I have enabled the employment of such drying powder in t-o'nnection with dresses of this-tvpe by the provision of 1nechanical means for applying the powder evenly and uniformly. Moreover, the starch or other, powder itself must be quickly and thoroughly removed from the cylinder as otherwise itwill cake thereon and, interf'ere with the obtaining of subsequent clear. impressions. and I have devised mechani-j ca'lly operating means for efii'ecting such removal.

The present invention relates to lmpro ed 46 means for elliciently.applying and removing the drying powder used to prevent offset,

and to that end' resides 'in the advantageous combination and arrangement of elements hereinafter claimed and as set forth in the accompanying drawing and detailed descriptiou by way of example, it being understood that the drawing and description are to be taken in an illustrative,rather than in an unnecessarily limiting sense. In the drawing is shown in a diagrammatic manner a perfecting press having the present invention associated therewith, thepress proper being shown in vertic'al section and the anti-offset device in side elevation.

, The reference numerals 1'1 and 12 designate respectively the first and second cylin' v ders the bed plate is indicated at 13, the feed at 1st, and the delivery at 15 will bereadily understood, the un- 50 printed sheet supplied to the cylinder 11 at l l is carried in, the direction indicated by the arrow upon the cylinder into contact with the bed plate where it receives upon its outer'face an impression. It then travels with the cylinder past the feed and as it reaches a point adjacent the cylinder. 1-2 is transferred from the first cylinder 11 to the second cylinder 12 and carried in the direction of the arrow upon the cylinder 12 into contact with the-bed plate 13 from which it receives upon its other face the-second impression, being removed from the cylinder 1 by-the delivery When the sheet is transferred from the cylinder 11 to the 'cylinder-lQ its freshly printed outer surface becomes the under surface in contact with the cylinder 12 and a certain amount oft he fresh ink is 1 transferred from the sheet to the cylinder. In order to prevent offsetting of this ink on to the freshly printed surface of the next sheet the present invention is devised and consists of a powder supply box 16 from which ihe ductor roll 17, vibrating between the positions shown in dotted and full lines takesthe powder and transfers it to a distributing roll 18 which in turn supplies the-powder to the applying rolls 19, 19. These latterrolls travel in c ntact with theperiphery of the cylinder 12 "and evenly apply the powder to the inked surface of the cylinder, and the powder acts instantaneously by absorption to take up the ink upon the cylinder surface. Arranged immediately after the powder ap plying rolls in the path of travel of the cyl inder and, closely adjacent thereto is an/ elongated suction nozzle 20 extending axially of the cylinder and with its open mouth close to the periphery thereof. A suction is 6 created through this nozzle by means of the exhaust device 21 acting through the pipe and discharging at 23. The nozzle 20 is preferably enveloped by a hood 24: and within the hood may advantageously be mounted suitably driven rotary brushes 25 and 26, by which the starch and ink adhering to the cylinder is loosened in readiness to be carried away by the suction.

It will be understood that the powderapplied to the periphery of the cylinder 12, having acted to dry by the suction nozzle and the surface of the cylinder left clean and dry in readiness-to receive from the cylinder 11 the next printed sheet. r

I claim:

1. In an anti-offset device. the combination with a press cylinder.

of mechanical means for applying powder transferring the powder. to the applying rolls. and pneumatic means act'inn' on the cylinder after the applying rolls to remove the powder, substantially. as described. 2. In an anti-offset device. the combination with a press cylinder. of mechanical means for applying powder thereto, said means'comprising' a powder box and a roll for applying powder to the cylinder. and pneumatic means acting on the cylinder after the applying roll to remove the powder, substantially as describ et 3. In an. antiofi'set device.' the combination with the second impression cylinder. of a perfecting press, of positive means for applying powder thereto, and pneumatic means including a suctionnozzle acting on the cylinder thereafter to remove the powder, substantially as described.

'l. In an anti-offset device. the combination with the second impression cylinder of a. perfecting, press, of positive .meansfor applying powder thereto, pneumatic means acting on the cylinder thereafter to remove the powder, said means comprising a nozzle having its mouth disposed adjacent the cylinder, and means to create an air current through said nozzle, substantially as described.

5. In an anti-offset device. the combination with the second impression cylinder of a perfecting press, of positive means for applyingpowder thereto, suction means acting on the cylinder in'imediately thereafter or blot the ink thereon, is thoroughly removed from the cylinder v thereto, said means comprising a powder boxnapplymg rolls, and a ductor roll for applying rolls, and a and means to substantion withthe second impression cylinder of a perfecting press, of means for applying powder thereto comprising a powder box. applying rolls, and a ductor roll for transferring the powder to the applying rolls, and pneumatic means acting on the cylinder after the applying rolls to remove the powdei'.'siibstantiall as described.

7. In an anti-offset tion with a cylinder, of means for applying powder thereto comprising" a powder box,

ductor roll for transferring the powder to the applying rolls. and suction means acting on .tl e'c linder immediately after the powder. applying means to remove the powder and comprising:

a suction nozzle ha ing! itsmouth disposed adjacent the cylinder. and means to create a suction'through the nozzle. substantially as described.

S. In an anti-oifset device; tion with a cylinder. ofni'eans for applying powder thereto comprising'a powder box. applying rolls. and aductor roll for transferrin; the po der ,to the and suction means acting onthe cylinder to remove the powder. said suction means comprisi ne' an elongated nozzle extending axially of the cylinder close to its periphery immediately after the powder applying means.- and means to create a suction" through the nozzle. substantially as de-- scribed.

In testimony whereof I have hereunto signed my name in the presence of two sill)- scribinn' witnesses.

CARL HFXDERSON'.

\Vitnesses:

H. M. Honnixs C. D. Gums.

of the cylin-- device, the combinathe conibina- I a pplying rolls. 

